Use of continuous positive airway pressure reduces airway reactivity in adults with asthma.

MedLine Citation:

PMID:
22835615
Owner:
NLM
Status:
Publisher

Abstract/OtherAbstract:

Asthma is characterized by airway hyper-reactivity, which is primarily treated with beta-adrenergic bronchodilators and anti-inflammatory agents. However, mechanical strain during breathing is an important modulator of airway responsiveness and we have previously demonstrated in animal models that continuous positive airway pressure (CPAP) resulted in lower in vivo airway reactivity. We now evaluated whether using nocturnal CPAP decreased airway reactivity in clinically-stable adults with asthma.Adults with stable asthma and normal spirometry used nocturnal CPAP (8-10 cmH2O) or SHAM (0-2 cmH2O) for 7-days. Spirometry and bronchial challenges were obtained before and after treatment. The primary outcome was PC20, the methacholine concentration that decreased FEV1 by 20%.CPAP group (N=16) had a significant decrease in airway reactivity (ΔlogPC20 = +0.406; p < 0.0017), while SHAM group (N=9) had no significant change in airway reactivity (ΔlogPC20 = 0.003; p=0.9850). There was a significant difference in the change in airway reactivity for CPAP vs. SHAM groups (+0.41; p < 0.043). Our findings indicate that chronic mechanical strain of the lungs produced using nocturnal CPAP for 7-days reduced airway reactivity in clinically stable asthmatics. Future studies of longer duration are required to determine whether CPAP can also decrease asthma symptoms and/or medication usage.